You previously used the Place Everywhere Previs repair tool, which generated Ppf.esm . Later, you uninstalled Place Everywhere or deleted the file manually, but another mod (or your save file) still expects it to be present.
PRP uses this master file to regenerate Precombines (merging multiple meshes into one to reduce draw calls) and Previs (preventing the game from rendering objects hidden behind walls), significantly boosting FPS. Fallout 4 Ppf.esm
For PPF.esm to work correctly and "tell a stable story" for your hardware, it generally follows this strict placement: You previously used the Place Everywhere Previs repair
and should be placed very high in your load order, typically right after the Unofficial Fallout 4 Patch and other major frameworks like Workshop Framework Dependencies : Many modern settlement mods (like Sim Settlements 2 For PPF